This invention relates to internal combustion engines, and more particularly to pistons used in such engines.
In two or four-cycle engines, such as the type used for lawn mowers and the like, magnesium may be used to make pistons when lightness of the piston is a major consideration. By using magnesium, the piston is approximately 30% lighter than a piston made from conventional materials. The lightness of magnesium causes less vibration in the two or four-cycle engine during operation. Lowering the vibration allows a more comfortable operation of an engine powered device.
The drawback to using magnesium in the piston is that the piston corrodes, erodes and sometimes burns. The moisture created in the combustion process tends to oxidize the magnesium and the heat generated tends to burn it.